Mobility scooter

[TOSS1]

Hiya all iam lee ive got a sterling s400 mobility scooter but up graded the controller unit to a 425 because of the lack of power/ speed and the wig wam but to no difference as any body out there got any more advice because iam at a lost now it was a 4mph and up to all new was to be 8mp but nar help needed

 

[Bluejets]

Wow...expensive tinkering........

Upgrading the controller probably make no difference as you want more power.

Perhaps larger motor and battery required as well.

Start up that route and cheaper to buy the whole 425 model.

 

[Delta Prime]

You're scooters is designed for maximum speed limit introducing a larger motor will increase your speed and torque for climbing up hills.
Also.. mobility scooters have a maximum weight capacity that will increase your weight and could very well cause damage to the physical frame of your scooter.
Upgrading your batteries to a higher current capacity will increase your speed along with perhaps different tires.
I have not researched your particular scooter but in general, mobility scooters have speed limiters that restricts your maximum speed.
One can disable the speed limiter "Viola!" more speed.